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The distributional ecology of the maned sloth: environmental influences on its distribution and gaps in knowledge.

Moreira Dde O, Leite GR, Ferreira de Siqueira M, Coutinho BR, Zanon MS, Mendes SL - PLoS ONE (2014)

Bottom Line: Our results suggest that the species distribution could be strongly influenced by environmental factors, mainly temperature seasonality.The modeled distribution of the maned sloth included known areas of occurrence in the Atlantic Forest (Sergipe, Bahia, Espírito Santo, and Rio de Janeiro), but did not match the observed distributional gaps in northern Rio de Janeiro, northern Espírito Santo or southern Bahia.Our results can be applied for novel surveys and discovery of unknown populations, and help the selection of priority areas for management and conservation planning, especially of rare and relatively cryptic species directed associated with forested habitats.

View Article: PubMed Central - PubMed

Affiliation: Programa de Pós-graduação em Ciências Biológicas (Biologia Animal), Departamento de Ciências Biológicas, Universidade Federal do Espírito Santo, Vitória, Espírito Santo, Brazil.

ABSTRACT
The maned sloth Bradypus torquatus (Pilosa, Bradypodidae) is endemic to a small area in the Atlantic Forest of coastal Brazil. It has been listed as a threatened species because of its restricted geographic range, habitat loss and fragmentation, and declining populations. The major objectives of this study were to estimate its potential geographic distribution, the climatic conditions across its distributional range, and to identify suitable areas and potential species strongholds. We developed a model of habitat suitability for the maned sloth using two methods, Maxent and Mahalanobis Distance, based on 42 occurrence points. We evaluated environmental variable importance and the predictive ability of the generated distribution models. Our results suggest that the species distribution could be strongly influenced by environmental factors, mainly temperature seasonality. The modeled distribution of the maned sloth included known areas of occurrence in the Atlantic Forest (Sergipe, Bahia, Espírito Santo, and Rio de Janeiro), but did not match the observed distributional gaps in northern Rio de Janeiro, northern Espírito Santo or southern Bahia. Rather, the model showed that these areas are climatically suitable for the maned sloth, and thus suggests that factors other than climate might be responsible for the absence of species. Suitable areas for maned sloth were located mainly in the mountainous region of central Rio de Janeiro throughout Espírito Santo and to the coastal region of southern Bahia. We indicate 17 stronghold areas and recommended survey areas for the maned sloth. In addition, we highlight specific areas for conservation, including the current network protected areas. Our results can be applied for novel surveys and discovery of unknown populations, and help the selection of priority areas for management and conservation planning, especially of rare and relatively cryptic species directed associated with forested habitats.

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Related in: MedlinePlus

Rescaled environmental variables, representing predicted and not predicted values of presence of the maned sloth.Standardization of environmental variables to the same scale (0 to 1), based on the potential geographic distribution modeling for the Atlantic Forest. The whiskers represent the mean ± standard deviation of the pixels from areas that the model did not predict the presence of maned sloth. The boxes represent the mean ± standard deviation of the pixels from predicted suitable areas for the presence of maned sloth. Elevation (ELV), mean monthly temperature range (TMR), temperature seasonality (TS), maximum temperature of warmest month (TWM), minimum temperature of coldest month (TCM), temperature annual range (TAR), annual precipitation (PA), precipitation of wettest month (PWM) and precipitation of driest month (PDM).
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pone-0110929-g004: Rescaled environmental variables, representing predicted and not predicted values of presence of the maned sloth.Standardization of environmental variables to the same scale (0 to 1), based on the potential geographic distribution modeling for the Atlantic Forest. The whiskers represent the mean ± standard deviation of the pixels from areas that the model did not predict the presence of maned sloth. The boxes represent the mean ± standard deviation of the pixels from predicted suitable areas for the presence of maned sloth. Elevation (ELV), mean monthly temperature range (TMR), temperature seasonality (TS), maximum temperature of warmest month (TWM), minimum temperature of coldest month (TCM), temperature annual range (TAR), annual precipitation (PA), precipitation of wettest month (PWM) and precipitation of driest month (PDM).

Mentions: We describe the habitat suitability of maned sloth as between 0 and 2,349.86 m of altitude, with an annual temperature between 8.5 and 19.4°C, and an annual precipitation between 753.01 and 2,592.0 mm. Table 1 shows the mean, maximum and minimum values of the environmental variables of suitable areas for B. torquatus, and table 2 shows the values for the most limiting environmental variables in areas of high probability of suitable conditions (Threshold>0.658). Comparison of environmental variables’ values among areas predicted as suitable and unsuitable reveals that temperature variation (such as monthly temperature range, seasonality, and annual range) presented quite-distinct values, showing that those variables are important to describe the climatic suitable areas for the maned sloth (Figure 4).


The distributional ecology of the maned sloth: environmental influences on its distribution and gaps in knowledge.

Moreira Dde O, Leite GR, Ferreira de Siqueira M, Coutinho BR, Zanon MS, Mendes SL - PLoS ONE (2014)

Rescaled environmental variables, representing predicted and not predicted values of presence of the maned sloth.Standardization of environmental variables to the same scale (0 to 1), based on the potential geographic distribution modeling for the Atlantic Forest. The whiskers represent the mean ± standard deviation of the pixels from areas that the model did not predict the presence of maned sloth. The boxes represent the mean ± standard deviation of the pixels from predicted suitable areas for the presence of maned sloth. Elevation (ELV), mean monthly temperature range (TMR), temperature seasonality (TS), maximum temperature of warmest month (TWM), minimum temperature of coldest month (TCM), temperature annual range (TAR), annual precipitation (PA), precipitation of wettest month (PWM) and precipitation of driest month (PDM).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4206454&req=5

pone-0110929-g004: Rescaled environmental variables, representing predicted and not predicted values of presence of the maned sloth.Standardization of environmental variables to the same scale (0 to 1), based on the potential geographic distribution modeling for the Atlantic Forest. The whiskers represent the mean ± standard deviation of the pixels from areas that the model did not predict the presence of maned sloth. The boxes represent the mean ± standard deviation of the pixels from predicted suitable areas for the presence of maned sloth. Elevation (ELV), mean monthly temperature range (TMR), temperature seasonality (TS), maximum temperature of warmest month (TWM), minimum temperature of coldest month (TCM), temperature annual range (TAR), annual precipitation (PA), precipitation of wettest month (PWM) and precipitation of driest month (PDM).
Mentions: We describe the habitat suitability of maned sloth as between 0 and 2,349.86 m of altitude, with an annual temperature between 8.5 and 19.4°C, and an annual precipitation between 753.01 and 2,592.0 mm. Table 1 shows the mean, maximum and minimum values of the environmental variables of suitable areas for B. torquatus, and table 2 shows the values for the most limiting environmental variables in areas of high probability of suitable conditions (Threshold>0.658). Comparison of environmental variables’ values among areas predicted as suitable and unsuitable reveals that temperature variation (such as monthly temperature range, seasonality, and annual range) presented quite-distinct values, showing that those variables are important to describe the climatic suitable areas for the maned sloth (Figure 4).

Bottom Line: Our results suggest that the species distribution could be strongly influenced by environmental factors, mainly temperature seasonality.The modeled distribution of the maned sloth included known areas of occurrence in the Atlantic Forest (Sergipe, Bahia, Espírito Santo, and Rio de Janeiro), but did not match the observed distributional gaps in northern Rio de Janeiro, northern Espírito Santo or southern Bahia.Our results can be applied for novel surveys and discovery of unknown populations, and help the selection of priority areas for management and conservation planning, especially of rare and relatively cryptic species directed associated with forested habitats.

View Article: PubMed Central - PubMed

Affiliation: Programa de Pós-graduação em Ciências Biológicas (Biologia Animal), Departamento de Ciências Biológicas, Universidade Federal do Espírito Santo, Vitória, Espírito Santo, Brazil.

ABSTRACT
The maned sloth Bradypus torquatus (Pilosa, Bradypodidae) is endemic to a small area in the Atlantic Forest of coastal Brazil. It has been listed as a threatened species because of its restricted geographic range, habitat loss and fragmentation, and declining populations. The major objectives of this study were to estimate its potential geographic distribution, the climatic conditions across its distributional range, and to identify suitable areas and potential species strongholds. We developed a model of habitat suitability for the maned sloth using two methods, Maxent and Mahalanobis Distance, based on 42 occurrence points. We evaluated environmental variable importance and the predictive ability of the generated distribution models. Our results suggest that the species distribution could be strongly influenced by environmental factors, mainly temperature seasonality. The modeled distribution of the maned sloth included known areas of occurrence in the Atlantic Forest (Sergipe, Bahia, Espírito Santo, and Rio de Janeiro), but did not match the observed distributional gaps in northern Rio de Janeiro, northern Espírito Santo or southern Bahia. Rather, the model showed that these areas are climatically suitable for the maned sloth, and thus suggests that factors other than climate might be responsible for the absence of species. Suitable areas for maned sloth were located mainly in the mountainous region of central Rio de Janeiro throughout Espírito Santo and to the coastal region of southern Bahia. We indicate 17 stronghold areas and recommended survey areas for the maned sloth. In addition, we highlight specific areas for conservation, including the current network protected areas. Our results can be applied for novel surveys and discovery of unknown populations, and help the selection of priority areas for management and conservation planning, especially of rare and relatively cryptic species directed associated with forested habitats.

Show MeSH
Related in: MedlinePlus